Targeted Use of Kudzu for Binge Drinking Among Adults With Alcohol Use Disorder: A Phase 2b Randomized Trial

OBJECTIVE: The aim of this study was to determine the efficacy and acceptability of targeted use of kudzu, an herbal supplement, in adults with alcohol use disorder (AUD) who binge drink. METHODS: In a double-blind placebo-controlled trial, 120 adults with AUD who binge drink were randomized in a 1:1 ratio to targeted (as-needed) use of oral kudzu extract (2 grams taken on days when binge drinking was anticipated) or matching placebo, plus weekly counseling for 12 weeks. The primary outcome was number of binge-drinking days in the past week. Prespecified secondary outcomes included number of self-reported binge-drinking weeks, number of drinks, and measurements of changes in alcohol use using biomarkers, including ethyl glucuronide (EtG) and phosphatidylethanol (PEth). RESULTS: Retention was high: 88% completed the trial, and 86% of weekly follow-up visits were completed. In the primary intention-to-treat (ITT) analysis, assignment to kudzu versus placebo reduced number of binge-drinking days (incidence rate ratio [IRR]=0.73, 95% CI=0.54, 0.99); as-treated (taking medication ≥2.7 days per week) analysis estimated a stronger effect (IRR=0.58, 95% CI=0.38, 0.89). Secondary outcomes showed lower number of binge-drinking weeks in ITT analysis (relative risk [RR]=0.79, 95% CI=0.62, 0.99). In as-treated analyses, reductions in number of binge-drinking weeks (RR=0.68, 95% CI=0.47, 0.98) and PEth positivity (RR=0.82, 95% CI=0.67, 0.99) were also significant. The number of binge-drinking days showed significant sustained reductions at the 3-month posttreatment visit (RR=0.68, 95% CI=0.47, 0.97). The overall frequency of adverse events was similar between groups. No serious adverse events related to kudzu occurred during follow-up. CONCLUSIONS: Targeted use of kudzu reduced self-reported binge-drinking outcomes among adults with AUD during treatment compared to placebo. Greater reductions in binge drinking and PEth were observed among those who took medication more frequently. Reductions in self-reported binge drinking persisted at the posttreatment visit. Kudzu may be a helpful pharmacologic treatment for binge drinking among people with AUD.